what you could do is just do a small amount at a time, and store the rest of the sand bag, all you do is put it in a saucepan and pop it in low heat for a while, it drys it out, theres nothing in the sand, and a quick wash she will never know!
maybe you can check on ebay or amazon for over there, there might be a way of getting the chinchilla sand rather then dust.
i have used our 'pets at home' chinchilla powder, its finer granules then sand, and dusty when you pour it out, but once the dust is gone it was ok.
I love the things you make
I have seen quite a few and I think its such a lovely idea to make things for them